3957939891091 has 2 divisors, whose sum is σ = 3957939891092. Its totient is φ = 3957939891090.

The previous prime is 3957939891043. The next prime is 3957939891127. The reversal of 3957939891091 is 1901989397593.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 3957939891091 - 2¹³ = 3957939882899 is a prime.

It is not a weakly prime, because it can be changed into another prime (3957939891991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1978969945545 + 1978969945546.

It is an arithmetic number, because the mean of its divisors is an integer number (1978969945546).

Almost surely, 2^{3957939891091} is an apocalyptic number.

3957939891091 is a deficient number, since it is larger than the sum of its proper divisors (1).

3957939891091 is an equidigital number, since it uses as much as digits as its factorization.

3957939891091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 148803480, while the sum is 73.

The spelling of 3957939891091 in words is "three trillion, nine hundred fifty-seven billion, nine hundred thirty-nine million, eight hundred ninety-one thousand, ninety-one".